Propylene polymer composition, film, stretched film, shrink film and a method for producing shrink package
AssigneeMitsui Chemicals, Inc.
InventorsTakayuki Kuroki, Norihide Inoue
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Abstract
A propylene polymer resin composition characterized in that it has a flexural modulus in the range of 200 to 1200 MPa and a melt flow rate (MFR) measured at 230° C. in the range of 0.1 to 30 g/min, and a melt tension (MT (mN)) and an MFR (g/10 min) measured at 230° C. satisfy a specific formula, and a sheet or film obtained therefrom. According to the present invention, there is provided a polyolefin film which is excellent in transparency and especially excellent in transparency and low-temperature heat shrinkable properties after stretching.
Claims12
A propylene polymer composition (X), wherein said propylene polymer composition (X) has a flexural modulus in the range of 200 to 1200 MPa and a melt flow rate (MFR) measured at 230° C. in the range of 0.1 to 30 g/10 min, and a melt tension (MT (mN)) and an MFR (g/10 min) measured at 230° C. satisfy the following formula:
- −0.773 log(MFR)+1.55≦log(MT)≦−0.773 log(MFR)+3.0.
A propylene polymer composition (Y), wherein said propylene polymer composition (Y) comprises 10 to 90% by weight of a propylene (co)polymer (A) which has a melting point in the range of 110 to 170° C. and a melt flow rate (MFR) measured at 230° C. in the range of 0.01 to 10 g/10 min and 90 to 10% by weight of a copolymer (B) of propylene and an a-olefin having 2 to 20 carbon atoms (excluding propylene) which has a melting point in the range of 40 to 100° C. and a melt flow rate (MFR) measured at 230° C. in the range of 0.5 to 50 g/10 min (here, the sum of the (co)polymer (A) and the copolymer (B) of propylene and an α-olefin having 2 to 20 carbon atoms (excluding propylene) is set equal to 100% by weight).
A shrink film obtained by stretching a sheet or film comprising a propylene (co)polymer (A1) having a melting point in the range of 110 to 170° C., a melt flow rate (MFR) measured at 230° C. in the range of 0.01 to 10 g/min and a melt tension in the range of 30 to 200 mN in at least one direction by 1.5 times or more.
Dependencies are inferred from the claim text.